TWI454815B - Electrophoretic display device and method for manufacturing the same - Google Patents

Description

Electrophoretic display device and method of manufacturing same

The present invention relates to an electrophoretic display device, and more particularly to an electrophoretic display device and a method of fabricating the same that can improve yield and reliability and reduce cost.

An electrophoretic display device is generally a device that can display an image by electrophoresis, in which a color charge particle can be moved by an electric field formed by the outside. Here, the term "electrophoresis" refers to a phenomenon in which an electric field is caused to move by a Coulomb force when an electric field is applied to an electrophoretic diffusion liquid (electrophoretic ink) having diffused charge particles therein.

This electrophoretic display device uses an electrophoresis technique that can display an original image for a longer period of time even when the applied voltage is shifted. In other words, such an electrophoretic device can maintain a specified picture for a longer period of time without constantly applying a voltage. Therefore, such an electrophoretic display device can be used as an electronic book that does not require a quick change of pictures.

Moreover, such an electronic display device does not rely on a viewing angle and can display an image that is generally suitable for viewing like paper, which is the difference between it and a liquid crystal display device. Therefore, the demand for such an electrophoretic display device is increasing due to the property of being bendable, low in energy consumption, and not damaging the environment.

According to the structure of the electrophoretic layer (or electrophoresis film), the electrophoretic display device can be divided into a microcapsule type electrophoretic display device and a microcup type electrophoretic display device.

Fig. 1 is a cross-sectional view showing the structure of a conventional microcapsule type electrophoretic display device. As shown in FIG. 1, the microcapsule-type electrophoretic display device includes an underlying substrate 10 and an upper substrate 20 bonded to each other, and an electrophoretic layer 30 between the lower substrate 10 and the upper substrate 20.

The electrophoretic layer 30 includes: a first bonding layer 34 formed of a transparent material; a second bonding layer 36; and a common electrode 38 disposed between the first bonding layer 34 and the second bonding layer 36; A plurality of microcapsules 32 having charged particles and an electrophoretic diffusion liquid. Although not shown in FIG. 1, the lower substrate includes a plurality of pixel electrodes opposed to the common electrode 38; and a plurality of thin film transistors (TFT) are used as these. A switching device for applying electrophoresis to the pixel electrode.

Here, the microcapsule 32 includes a dielectric solution, positive particles (+) and negative particles (-). The charged particles disposed in the microcapsules 32 can be moved in the dielectric solution to display an image.

In the electrophoretic display device shown in "Fig. 1", the lower substrate 10, the upper substrate 20, and the electrophoretic layer 30 can be separately manufactured. Then, the electrophoretic layer 30 can be placed between the lower substrate 10 and the upper substrate 20.

Here, the electrophoretic layer 30 can be connected to the upper substrate 20 through the second bonding layer 36, and a spacer film can be connected through the first bonding layer 34. Wherein, the separator may be laminated on the first adhesive layer 34 or the arrangement of the separator may be cancelled. Then, the electrophoretic layer 30 can be connected to the underlying substrate 10 through the first bonding layer 34.

As described above, since the lower substrate 10, the upper substrate 20, and the electrophoretic layer 30 must be separately formed, the manufacturing process of such an electrophoretic display device is very complicated. Therefore, the manufacturing method of such an electrophoretic display device requires a long time and has a disadvantage of low yield. At the same time, there is a drawback that the manufacturing cost of the electrophoretic film 30 is increased.

Fig. 2 is a cross-sectional view showing the structure of a conventional microcup type electrophoretic display device. As shown in FIG. 2, the microcup type electrophoretic display device includes an upper substrate 40, a lower substrate 50, and an electrophoretic layer built in the lower substrate 50.

Here, the upper substrate 40 includes: a substrate 42 (or a base film) formed of a transparent material; and a common electrode 44 made of a transparent conductive material such as indium tin oxide (ITO) or zinc indium oxide. (IZO, Indium Zinc Oxide) formed.

The lower substrate 50 includes a substrate 52 formed of a transparent or translucent material, and a plurality of pixel electrodes 54 disposed on the substrate 52 and facing the common electrode 44. Here, a plurality of thin film transistors (not shown) as switching means may be formed on the substrate 52 to apply voltages to the pixel electrodes 54.

The electrophoretic layer includes: a plurality of partition walls 56 for defining sub-pixels formed on the lower substrate 50 to display images; and an electrophoretic diffusion liquid 62 (or electrophoretic ink), which are injected into the electrophoretic diffusion liquid. In the sub-picture. Here, these electrophoretic diffusion liquids 62 include a dielectric solution and a plurality of charged particles 64. The charge particles 64 in the dielectric solution are movable along an electric field formed by the common electrode 44 and the pixel electrode 54.

In the microcup type electrophoretic display device having the above structure, the electrophoretic diffusion liquid 62 can be injected into the subpixel defined by the partition wall 56 formed on the lower substrate 50. In other words, the electrophoretic diffusion liquid 62 can be built in the lower substrate 50.

Here, when the partition wall 56 is formed of an inorganic material, the electrophoretic diffusion liquid 62 cannot be filled with the electrophoretic diffusion liquid and bubbles are generated during the filling process of the electrophoretic diffusion liquid 62 as shown in "Fig. 3".

Further, such an electrophoretic display device has a sealant located in an outer region of a display region formed on the lower substrate 50, and a sealant for bonding the upper substrate 40 and the lower substrate 50. However, a guide for preventing the overflow of the sealant from flowing to the outside and the outside of the sealant application region has not been formed.

Therefore, the sealant for joining the upper substrate 40 and the lower substrate 50 can overflow into the inside and the outside of the display panel shown in FIG. 4, and the operation error can be caused. At the same time, if such a sealant overflows into the inside and the outside of the display panel, the bonding process of the upper substrate 40 and the lower substrate 50 cannot be smoothly and successfully performed.

In addition, the overflow of the sealant may make the display panel unable to be completely enclosed with respect to the outside, and may cause the electrophoretic display device to be contaminated by outside air and moisture. Therefore, the defects formed by the overflow of the sealant bonded to the upper substrate and the lower substrate can reduce the yield and reliability of the electrophoretic display device.

Accordingly, the present invention provides an electrophoretic display device and a method of fabricating the same.

An object of the present invention is to provide an electrophoretic display device and a method of fabricating the same, thereby providing a yield.

Another object of the present invention is to provide an electrophoretic display device and a method of fabricating the same, thereby reducing cost.

It is still another object of the present invention to provide an electrophoretic display device and a method of fabricating the same, thereby simultaneously providing high productivity and reliability of the electrophoretic display device.

Still another object of the present invention is to provide an electrophoretic display device and a method of manufacturing the same, which prevent defects caused by overflow of an electrophoretic diffusion liquid (electrophoretic ink) built in a lower substrate to a peripheral portion of a display panel.

Still another object of the present invention is to provide an electrophoretic display device and a method of manufacturing the same, which prevent a sealant for bonding an upper substrate and a lower substrate to each other to overflow inside or outside the display panel to cause defects.

It is still another object of the present invention to provide an electrophoretic display device comprising an underlying substrate on which an electrophoretic diffusion liquid is built.

Still another object of the present invention is to provide a method of manufacturing an electrophoretic display device in which an electrophoretic diffusion liquid can be built in a lower substrate.

It is still another object of the present invention to provide an electrophoretic display device and a method of fabricating the same that obtain a high quality display image.

It is still another object of the present invention to provide an electrophoretic display device and a method of fabricating the same, thereby displaying a plurality of color images.

Other advantages, objects, and features of the invention will be set forth in part in the description which follows, It is understood or can be derived from the practice of the invention. The objectives and other advantages of the invention will be realized and attained by the <RTI

In order to achieve the objects and other features of the present invention, the present invention is embodied and described in detail. An electrophoretic display device of the present invention comprises: an underlying substrate having a plurality of pixel electrodes formed on the underlying substrate And a plurality of partition walls formed on the lower substrate and surrounding the respective pixel electrodes, wherein the pixel electrodes and the partition walls define a plurality of sub-pixels; the upper substrate is bonded to the lower substrate, wherein The upper substrate has a common electrode, and a sealing layer is formed on a region of the common electrode corresponding to the pixel electrodes; the electrophoretic diffusion liquid contains a plurality of charged particles, and the charged particles are dyed into a predetermined color to be displayed. Wherein, the electrophoretic diffusion liquid is injected through the pixel electrodes and the sub-pixels defined by the partition walls; and the interlayer is formed between the sealing layer and the electrophoretic diffusion liquid.

Another aspect of the present invention provides a method of fabricating an electrophoretic display device, comprising: forming a plurality of sub-pixels by forming a plurality of partition walls on a lower substrate, wherein the partition wall surrounds a plurality of pixels formed on the lower substrate a pixel of each of the electrodes; forming a sealing layer on a region of the common electrode of the upper substrate corresponding to the sub-pixels; filling the electrophoretic diffusion liquid to a sub-picture defined by the pixel electrode and surrounded by the partition wall Wherein the electrophoretic diffusion liquid comprises a plurality of charged particles, the charged particles are dyed to a predetermined color to be displayed; an interlayer is formed between the sealing layer and the electrophoretic diffusion liquid; and the interlayer between the upper substrate and the lower substrate is passed through The upper substrate is combined with the lower substrate, wherein the interlayer is formed on the upper substrate or the lower substrate.

It is to be understood that the summary of the present invention is not intended to limit the scope of the subject matter of the claimed subject matter.

Hereinafter, embodiments of the present invention will be specifically described with reference to the accompanying drawings showing examples of the present invention. In the drawings, the same component symbols represent the same components. Hereinafter, an electrophoretic display device of the present invention and a method of manufacturing the same will be described with reference to the accompanying drawings. However, when a structure is disclosed in the embodiment of the present invention and a structure is located on another structure or a lower jaw, it can be understood that the two structures are in contact with each other or have a third structure in the two. between.

At the same time, the technical subject matter of the present invention is applicable to all types of electrophoretic display devices regardless of whether or not the colors are expressed. For convenience of description, a color electrophoretic display device will be described below as an example.

Here, the electrophoretic display device disclosed in the present invention includes a monochrome electrophoretic display device and an electrophoretic display device including a color filter. In other words, the charged particles provided in the electrophoretic diffusion liquid (electrophoretic ink) can be dyed through one of red, green, yellow, cyan, magenta, black, and white.

Meanwhile, the present invention is also applicable to the microcapsule type electrophoretic display device shown in "Fig. 1" and the microcup type electrophoretic display device shown in "Fig. 2". Hereinafter, the present invention will be explained by taking a microcup type electrophoretic display device as an example.

Fig. 5 is a schematic view showing the configuration of an electrophoretic display device according to an embodiment of the present invention. As shown in FIG. 5, the electrophoretic display device 100 of the embodiment of the present invention includes an upper substrate 110 having a first substrate 112, a common electrode 114, and a sealing layer 116 formed on the common electrode. The lower substrate 120 has A plurality of pixel electrodes 124, a partition wall 126, and an electrophoretic diffusion liquid 130 formed on the pixel electrode. Here, the electrophoretic diffusion liquid 130 may be built in a plurality of sub-pixels defined by the partition wall 126, and an interlayer 128 may be formed to prevent the electrophoretic diffusion liquid 130 from directly contacting the sealing layer formed on the upper substrate 110. . Wherein, the partition walls 126 of the sub-pixels may have adjacent individual structures.

In the electrophoretic display device 100 of the embodiment of the present invention, the sub-pixels are filled by the charge particles 132, and the voltage applied to the common electrode 114 and the pixel electrodes 124 is placed in the sub-pixel in the dielectric solution. The charged particles 132 generate motion to produce a monochrome image and a color image. The upper substrate 110 includes: a first substrate 112 (or a base film) formed of transparent glass or plastic; a common electrode 114 formed on the first substrate 112; and a sealing layer 116 for The electrophoretic diffusion liquid 130 is built in the upper substrate 110 and is used to connect the upper substrate 110 and the lower substrate 120 to each other.

Here, the first substrate 112, the common electrode 114, and the sealing layer 116 constituting the upper substrate 110 must be transparent to display an image. Therefore, the first substrate 112 can be formed through the flexible transparent material, and the common electrode 114 can be formed through a transparent conductive material such as Indium Tin Oxide (ITO) or Indium Zinc Oxide (IZO). The sealing layer 116 may be formed on the common electrode 114 of the upper substrate 110 and on a predetermined region corresponding to the image displayed by the sub-pixel.

Here, the sealing layer 116 is used to seal the electrophoretic diffusion liquid 130. The transparent material may be applied to the common electrode 114 of the upper substrate 110, and the coated material corresponding to the sub-pixels may be patterned by a light micro-etching process to form the sealing layer 116. Alternatively, the sealing layer 116 may be formed by a roll-to-roll process using a reel having an embossed engraving pattern. Here, the material for forming the sealing layer 116 on the upper substrate 110 may be the same as or different from the material for forming the partition wall 126 to be described later.

Here, the lower substrate 120 includes a second substrate 122 (or a base film), a pixel electrode 124, a partition wall 126, an electrophoretic diffusion liquid 130, and an interlayer 128. At the same time, a plurality of gate lines (not shown) and a plurality of data lines (not shown) may be formed on the second substrate 122, and respectively formed at intersections of the data lines and the gate lines. Thin film transistor (not shown). Further, the electrophoretic diffusion liquid 130 can be injected into the sub-pixel defined by the partition wall 126 built in the lower substrate 120.

The second substrate 122 is formed by a transparent glass substrate, a flexible plastic substrate or a metal substrate. At the same time, since the second substrate 122 is located on the opposite side of the screen on which the image is displayed, the second substrate 122 does not have to be transparent.

Here, each of the gate lines and each of the data lines having a single layer structure is formed by silver (Ag), aluminum (Al) or silver-aluminum alloy having a lower resistance value. Alternatively, a gate line and a data line of a multilayer structure having a single layer and another layer formed by passing chromium (Cr), titanium (Ti) or tantalum (Ta) having excellent conductive properties may be included.

In addition, a gate insulating film may be formed through a nitride layer between the gate line and the data line. At the same time, a thin film transistor can be formed at each intersection between the gate line and the data line. Here, the gate of the thin film transistors can be connected to the gate line, and the source of the thin film transistor is connected to the data line. At the same time, the drain of the thin film transistor can be connected to the pixel electrode 124.

Here, the pixel electrodes 124 may correspond to a plurality of sub-pixels defined by the partition wall 126. Further, the pixel electrode 124 can apply a voltage to the sub-pixel by a switching operation of the thin film transistor. At the same time, the pixel electrodes 124 can be electrically connected to the drains of the thin film transistor through the contact holes. Among them, these pixel electrodes 124 can be formed by, for example, materials such as copper, aluminum, and indium tin oxide. Alternatively, the pixel electrode may be a multilayer structure formed of a nickel layer and/or a gold layer on a layer formed of copper, aluminum or indium tin oxide.

Further, a partition wall 126 may be formed on the lower substrate 120 to define a plurality of sub-pixels. Wherein, the partition wall 126 can surround the pixel electrode 124 to define the sub-pixel. Here, the partition wall 126 can be formed by a non-polar organic material having the same physical properties as the electrophoretic diffusion liquid 130 built in the sub-pixel. For example, the partition wall 126 and the electrophoretic diffusion liquid 130 may contain a dielectric solution having no polarity. At the same time, the partition wall 126 having a height of 1 μm to 100 μm can be formed by a photo-inscription technique or a molding printing technique. As described above, the partition walls 126 formed on the lower substrate 120 can have adjacent independent structures.

Further, the electrophoretic diffusion liquid 130 including the plurality of charged particles 132 and the dielectric solution may be injected into the sub-pixel defined by the partition wall 126. In other words, the electrophoretic diffusion liquid 130 can be built in the lower substrate 120. Here, the underlying substrate 120 may be filled with the electrophoretic diffusion liquid 130 by a slit coating method, a casting method, a roll coating method, a dispensing method, an extrusion method, a screen printing method, a spray method, or a light micro-engraving method. Form a sub-pixel on it.

The electrophoretic diffusion liquid 130 may include: a dielectric solution having no polarity; and a plurality of charged particles 132 charged through the positive electrode (+) or the negative electrode (−). In other words, one portion of the charge particles 132 has a positive polarity (+) and the other charge particles 132 have a negative polarity (-) by charging. The charge particles 132 may be dyed by at least one of red, green, yellow, cyan, magenta, black, and white.

Here, if the outer wall surrounding the electrophoretic diffusion liquid 130 has different physical properties from the treated electrophoretic diffusion liquid 130, it means that the electrophoretic diffusion liquid 130 is not completely injected. Therefore, this incomplete filling condition occurs and defects are generated due to bubbles generated during the filling process.

As described above, the physical properties of the organic material of the electrophoretic diffusion liquid 130 included in the electrophoretic display device of the embodiment of the present invention and the outer wall surrounding the electrophoretic diffusion liquid 130 built in the lower substrate 120, that is, the physical properties of the partition wall 126 organic material. The same characteristics. For example, the dividing wall 126 and the dielectric fluid may be non-polar.

Therefore, the process of embedding the electrophoretic diffusion liquid 130 on the lower substrate 120 can be smoothly performed while preventing a failure in the bonding process between the upper substrate 110 and the lower substrate 120.

Further, since the electrophoretic diffusion liquid 130 is built in the lower substrate 120, the driving stability of the electrophoretic display device can be improved.

In addition, since the charge particles 132 can be dyed through a plurality of colors, a plurality of color images can be displayed, and the display quality of the electrophoretic display device can be improved.

Here, if the charge particles 132 are directly in contact with the sealing layer 116, a failure occurs in the original arrangement or a malfunction occurs in the electrochemical characteristics. In other words, even if an electric field is applied to the sub-pixels in such a situation, the charge particles 132 cannot be moved and an error in image display failure may occur. Therefore, in order to prevent the charged particles 132 from coming into direct contact with the sealing layer 116, the interlayer 128 corresponding to the sealing layer 116 on the upper substrate 110 may be formed. Here, the sealing layer 116 and the interlayer 128 have non-polarization characteristics.

Therefore, the interlayer 128 can be formed on the partition wall 126, and the sub-pixels can be filled by the electrophoretic diffusion liquid 130. Here, a film formed by an insulating organic material having a thickness of several nanometers may be used as the interlayer 128. For example, the interlayer 128 can be formed by methyl ethyl ketone (MEK, Methyl Ethyl Ketone). At the same time, a light yellow color can also be added to the interlayer 128 to increase the contrast.

In order to form the interlayer 128, the partition wall 126 may be coated with a transparent material such as methyl ethyl ketone, and the sub-pixels may be filled by the electrophoretic diffusion liquid 130. An imprinting process or a photolithography process can then be performed on the coated transparent material to form the interlayer 128. Alternatively, the interlayer 128 may be formed by a roll-to-roll process using a reel having an embossed engraving pattern.

In the embodiment of the present invention, the interlayer 128 may be formed on the lower substrate 120. In another embodiment of the invention, the charge particles 132 are prevented from coming into direct contact with the sealing layer 116 through the interlayer 128. Meanwhile, at the point where the interlayer 128 is formed, there is no limitation on the substrate (the upper substrate 110 or the lower substrate 120).

In the electrophoretic display device 100 of the embodiment of the present invention having the above configuration, the upper substrate 110 and the lower substrate 120 can be bonded through the sealing layer 116 of the upper substrate 110. Therefore, such an electrophoretic display device can prevent defects caused by overflow of a sealant for bonding the upper substrate and the lower substrate to each other.

In the meantime, in the embodiment of the present invention, the external air and moisture elements can be prevented from contaminating the electrophoretic display device through the completely sealed display panel. Therefore, the yield and reliability of such an electrophoretic display device can be improved.

Hereinafter, a method of manufacturing an electrophoretic display device according to an embodiment of the present invention will be described with reference to "Fig. 6a" to "Fig. 8".

"Fig. 6a" to "Fig. 6c" show a method of manufacturing the upper substrate of the electrophoretic display device in the embodiment of the present invention.

As shown in Fig. 6a, for example, indium tin oxide (ITO) or indium zinc oxide (IZO) may be used on the first substrate 112 (or base film) formed by transparent glass or flexible transparent plastic. A conductive material such as Indium Zinc Oxide) forms a common electrode 114.

As shown in "Fig. 6b", the first substrate 112 can be coated with a transparent material 115 to cover the common electrode 114.

Then, as shown in FIG. 6c, the transparent material 115 coated on the first substrate 112 can be patterned by an imprint process or a photolithography process to form the sealing layer 116. At this time, the sealing layer 116 corresponds to a sub-pixel for displaying an image.

Here, the transparent material for forming the sealing layer 116 on the upper substrate 110 may be the same as or different from the material for forming the partition wall 126 which will be described later. Alternatively, the sealing layer 116 may be formed by a roll-to-roll process using a reel having an embossed engraving pattern. Here, the sealing layer 116 and the partition wall 126 may have a non-polarity.

The method of manufacturing the upper substrate 110 of the electrophoretic display device according to the embodiment of the present invention has been described above with reference to "6a to 6c".

"7a" to "7d" are manufacturing methods of the underlying substrate of the electrophoretic display device according to the embodiment of the present invention. The time required for the process of the upper substrate 110 described in "Fig. 6a" to "Fig. 6c" and the time required for the process of the lower substrate 120 described in "Fig. 7a" to "Fig. 7d" The same, the bonding process of the upper substrate 110 and the lower substrate 120 can be performed smoothly and efficiently.

First, as shown in "Fig. 7a", copper, aluminum or indium tin oxide may be coated on the second substrate 122 (or base film) having a thin film transistor corresponding to a plurality of sub-pixels. Then, the applied copper, aluminum or indium tin oxide can be patterned by photolithography to form a plurality of pixel electrodes 124. At the same time, these pixel electrodes 124 can be respectively associated with a plurality of sub-pixels. Here, in order to form these pixel electrodes 124, a nickel layer and/or a gold layer may be further formed on the copper layer, the aluminum layer or the indium tin oxide layer, thereby constituting a multilayer structure. Further, a plurality of sub-pixels defined by the partition wall 126 can be manufactured through the following processes.

As shown in "Fig. 7b", the organic material may be coated on the second substrate 122 on which the pixel electrode 124 is formed. These organic materials can then be patterned to form a dividing wall 126. Further, sub-pixels to be filled with the electrophoretic diffusion liquid 130 can be defined by the partition wall 126.

Further, the partition wall 126 having a height of 1 μm to 100 μm can be formed by a photolithography technique or a mold printing technique. Here, the partition wall 126 may be in contact with the electrophoretic diffusion liquid 130 filling the sub-pixels. Therefore, the organic material used to form the partition wall 126 can have the same physical properties as the dielectric fluid contained in the electrophoretic diffusion liquid 130. For example, the partition wall 126 and the dielectric fluid may both be non-polar.

As shown in "Fig. 7c", the electrophoretic diffusion liquid 130 having the charged particles 132 charged through the positive electrode (+) or the negative electrode (-) can be injected into the sub-pixels defined by the partition wall 126. Therefore, the electrophoretic diffusion liquid 130 can be built in the lower substrate 120. Here, the underlying substrate 120 may be filled with the electrophoretic diffusion liquid 130 by a slit coating method, a casting method, a roll coating method, a dispensing method, an extrusion method, a screen printing method, a spray method, or a light micro-engraving method. Form a sub-pixel on it.

Then, as shown in "Fig. 7d", the interlayer 128 can be formed on the partition wall 126, and the sub-pixel corresponding to the sealing layer 116 on the upper substrate 110 can be filled by the electrophoretic diffusion liquid 130. For example, the interlayer 128 can be formed by methyl ethyl ketone.

The interlayer 128 is used to prevent the charged particles 132 from coming into contact with the sealing layer 116 of the upper substrate 110. Specifically, such a transparent material, for example, methyl ethyl ketone, may be applied to the partition wall 126 and the sub-pixels filled by the electrophoretic diffusion liquid 130. The coated transparent material can then be subjected to an engraving process or a photolithography process, and the interlayer 128 can be formed by an imprint process or a photolithography process. Alternatively, the interlayer 128 may be formed by a roll process having a embossed engraving pattern.

In the embodiment of the present invention, the interlayer 128 may be formed on the lower substrate 120. However, this does not limit the invention. In the embodiment of the present invention, the interlayer 128 may be formed on the upper substrate 110. In other words, the interlayer 128 can be formed on any one of the substrates (i.e., the upper substrate 110 or the lower substrate 120), and thus the structure can prevent the 132 from directly contacting the sealing layer 116. When the interlayer 128 is formed on the upper substrate 110, a transparent material can be applied to the sealing layer 116 shown in "Fig. 6c". The interlayer 128 can then be formed by an imprint process or a photolithography process.

The "Fig. 8" is a schematic view of a method for joining the upper substrate 110 and the lower substrate 120 to each other.

As shown in Figure 8, the reel-type process performed by the reel 140 allows the upper substrate 110 and the "7a to" to 7d charts shown in "Fig. 6a" to "6c". The lower substrate 120 is combined. At this time, the working condition of the reel type process is that a predetermined pressure is applied to the upper substrate 110 and the lower substrate 120, and an annealing process can be performed by applying a predetermined temperature to the upper substrate 110 and the lower substrate 120.

In the electrophoretic display device of the embodiment of the invention, the upper substrate and the lower substrate can be bonded to each other in accordance with the above method. Therefore, the bonding between the upper substrate and the lower substrate can be smoothly achieved, thereby simplifying the entire manufacturing process. Further, productivity is improved.

In addition, the upper substrate and the lower substrate of the electrophoretic display device of the embodiment of the present invention can be combined with each other by other methods without using a sealant. Further, the defects generated in the bonding process are reduced.

Therefore, the present invention can completely seal the display panel and prevent contamination of the electrophoretic display device due to external air and moisture factors. Therefore, the yield and reliability of the electrophoretic display device can be improved.

Meanwhile, in the embodiment of the present invention, the electrophoretic diffusion liquid may be built in the lower substrate 120. Therefore, the manufacturing cost of the electrophoretic display device can be reduced.

According to the above manufacturing method, the electrophoretic diffusion liquid can be injected into the sub-pixel surrounded by the partition wall, the upper substrate, and the lower substrate. At the same time, the outer wall surrounded by the electrophoretic diffusion liquid, that is, the partition wall is formed of an organic material. Therefore, the physical properties of the partition wall can be the same as those of the dielectric fluid contained in the electrophoretic diffusion liquid. Specifically, the partition wall and the dielectric fluid contained in the electrophoretic diffusion liquid may have non-polar characteristics.

Therefore, the process of embedding the electrophoretic diffusion liquid on the lower substrate can be made smoother and more efficient. Further, when the upper substrate and the lower substrate are bonded to each other, it is possible to prevent a malfunction in the sub-pixel.

Further, the method of manufacturing an electrophoretic display device according to an embodiment of the present invention has an advantage that a liquid crystal display can be formed through an internal structure.

Therefore, the present invention has various advantages. For example, the present invention can improve the yield of an electrophoretic display device. At the same time, the present invention can reduce the manufacturing cost of the electrophoretic display device. Here, the method for manufacturing an electrophoretic display disclosed by the present invention can also improve the yield and reliability of the electrophoretic display device. Further, the present invention can also prevent a malfunction caused by overflow of the electrophoretic diffusion liquid built in the substrate below the electrophoretic display device toward the peripheral portion of the display panel. Meanwhile, the present invention can also be used to prevent a malfunction caused by overflow of a sealant used for bonding an upper substrate and an underlying substrate of an opposite electrophoretic display device toward the inside or the outside of the display panel. Further, the present invention can improve the display quality of the electrophoretic display device. The present invention provides an electrophoretic display device comprising a substrate underlying an electrophoretic diffusion liquid. In addition, an embodiment of the present invention provides a method of manufacturing an electrophoretic display device, whereby an electrophoretic diffusion liquid is built in a lower substrate. At the same time, the present invention also provides a display device and a method of fabricating the same, thereby displaying images of a plurality of colors.

Although the present invention has been disclosed above in the foregoing embodiments, it is not intended to limit the invention. It is within the scope of the invention to be modified and modified without departing from the spirit and scope of the invention. Please refer to the attached patent application for the scope of protection defined by the present invention.

20, 40. . . Upper substrate

10, 50. . . Lower substrate

30. . . Electrophoretic layer

32. . . Microcapsules

34. . . First bonding layer

36. . . Second bonding layer

38. . . Common electrode

42, 52. . . Substrate

44. . . Common electrode

54. . . Pixel electrode

56. . . Partition wall

62. . . Electrophoretic diffusion fluid

64. . . Charge particle

100. . . Electrophoretic display device

110. . . Upper substrate

112. . . First substrate

114. . . Common electrode

115. . . Transparent material

116. . . Sealing layer

120. . . Lower substrate

122. . . Second substrate

124. . . Pixel electrode

126. . . Partition wall

128. . . Mezzanine

130. . . Electrophoretic diffusion fluid

132. . . Charge particle

140. . . reel

1 is a cross-sectional view showing the structure of a conventional microcapsule type electrophoretic display device;

2 is a cross-sectional view showing the structure of a conventional microcup type electrophoretic display device;

Figure 3 shows the failures caused by the incomplete filling of the electrophoretic diffusion liquid and the bubbles, respectively;

Fig. 4 shows a failure due to overflow of a sealant for bonding the upper substrate and the lower substrate;

FIG. 5 is a schematic diagram showing the structure of an electrophoretic display device according to an embodiment of the present invention; FIG.

6a to 6c are diagrams showing a method of manufacturing an upper substrate of an electrophoretic display device according to an embodiment of the present invention;

7a to 7d are diagrams showing a method of manufacturing a lower substrate of an electrophoretic display device according to an embodiment of the present invention;

Fig. 8 is a schematic view showing a method for bonding an upper substrate and a lower substrate to each other.

100. . . Electrophoretic display device

110. . . Upper substrate

112. . . First substrate

114. . . Common electrode

116. . . Sealing layer

120. . . Lower substrate

122. . . Second substrate

124. . . Pixel electrode

126. . . Partition wall

128. . . Mezzanine

130. . . Electrophoretic diffusion fluid

132. . . Charge particle

Claims (21)

An electrophoretic display device comprising: a lower substrate having a plurality of pixel electrodes formed on the lower substrate; and a plurality of partition walls formed on the lower substrate and surrounding the pixel electrodes Wherein the pixel electrodes and the partition walls define a plurality of sub-pixels; an upper substrate is bonded to the lower substrate, wherein the upper substrate has a common electrode, and the common electrode and the pixel electrodes a sealing layer is formed on the corresponding region; an electrophoretic diffusion liquid includes a plurality of charged particles, and the charged particles are dyed into a predetermined color to be displayed, wherein the electrophoretic diffusion liquid is injected through the pixel electrodes and The sub-pixels defined by the partition walls; and an interlayer formed between the sealing layer and the electrophoretic diffusion liquid, wherein the interlayer is used to prevent the electrophoretic diffusion liquid from directly forming on the upper substrate The sealing layer is in contact with the interlayer, wherein the interlayer is a film formed of an insulating organic material. The electrophoretic display device of claim 1, wherein the interlayer is formed on the sealing layer of the upper substrate. The electrophoretic display device of claim 1, wherein the interlayer is formed on the partition walls of the underlying substrate and the electrophoretic diffusion liquid. The electrophoretic display device of claim 1, wherein the sealing layer is transparent The material is formed. The electrophoretic display device of claim 1, wherein the partition walls are formed of an organic material having a height of 1 micrometer to 100 micrometers. The electrophoretic display device of claim 1, wherein the electrophoretic diffusion liquid is located in the sub-pixels surrounded by the partition walls. The electrophoretic display device of claim 1, wherein the charged particles are dyed by one of red, green, yellow, cyan, magenta, black, and white. The electrophoretic display device of claim 1, wherein a light yellow color is added to the interlayer to improve contrast. A method for manufacturing an electrophoretic display device, comprising: forming a plurality of sub-pixels by forming a plurality of partition walls on a lower substrate, wherein the partition walls surround each of a plurality of pixel electrodes formed on the lower substrate a pixel electrode; forming a sealing layer on a region of a common electrode of one of the upper substrates corresponding to the sub-pixels; filling an electrophoretic diffusion liquid to define and be divided by the pixel electrodes In the sub-pixel surrounded by the partition wall, wherein the electrophoretic diffusion liquid comprises a plurality of charged particles, the charged particles are dyed to a predetermined color to be displayed; and a sandwich layer is formed between the sealing layer and the electrophoretic diffusion liquid. And the upper layer is formed by the interlayer between the upper substrate and the lower substrate The substrate is combined with the underlying substrate, wherein the interlayer is formed on the upper substrate or the lower substrate, wherein the interlayer is used to prevent the electrophoretic diffusion liquid from directly contacting the sealing layer formed on the upper substrate, wherein the interlayer It is a film formed by an insulating organic material. The method of manufacturing an electrophoretic display device according to claim 9, wherein the upper substrate and the lower substrate are bonded to each other through a sealant, wherein the sealant surrounds a peripheral portion of a display region. The method of manufacturing an electrophoretic display device according to claim 9, wherein the interlayer is formed on the sealing layer of the upper substrate. The method of manufacturing an electrophoretic display device according to claim 9, wherein the interlayer is formed on the partition walls of the lower substrate and the electrophoretic diffusion liquid. The method for manufacturing an electrophoretic display device according to claim 9, wherein a transparent material is coated on the common electrode, and the applied transparent material is patterned by an imprinting process or a photolithography process to form a transparent material. The sealing layer. The method of manufacturing an electrophoretic display device according to claim 9, wherein the reel having one of the embossed engraving patterns forms the sealing layer through a reel process. The method of manufacturing an electrophoretic display device according to claim 9, wherein the material forming the sealing layer is the same as the material for forming the partition wall. The method of manufacturing an electrophoretic display device according to claim 9, wherein the material forming the sealing layer is different from a material for forming the partition wall. The method for manufacturing an electrophoretic display device according to claim 9, wherein a transparent material is coated on the partition wall, and the sub-pixels are filled through the electrophoretic diffusion liquid, and are processed by an imprint process or a photolithography process. The applied transparent material is patterned to form the sealing layer. The method of manufacturing an electrophoretic display device according to claim 9, wherein the partition walls having a height of 1 μm to 100 μm are formed by an imprinting process or a photolithography process. The method for producing an electrophoretic display device according to claim 9, wherein the slit coating method, the casting method, the reel coating method, the dispensing method, the extrusion method, the screen printing method, the spraying method, or the light micro-transmission method The electrophoretic diffusion liquid is filled into the sub-pixels by engraving. The method of manufacturing an electrophoretic display device according to claim 9, wherein the lower substrate and the upper substrate are bonded to each other through a roll-to-roll process. The method of manufacturing an electrophoretic display device according to claim 9, wherein a pale yellow color is added to the interlayer to improve contrast.